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I did't understood "memory map boundary is 4k ", through which means u r taking about ...
But in case of AMBA-AHB if any master is trying to cross 1K address boundary then its not allowded ,then it will go into break state.... So in AMBA-AHB it is 1K only.....For ref u can see AMBA Specification (Rev 2.0)
Thanks in advance.....
as i know, AHB Slave space should not less than 1KB, the reason lies on simple decoder design. You need only decode 20-bit address signals, not full 32-bit.
If there has no constraints about burst address, when one AHB burst transfer is going, it may go across 1KB boundary, run into another slave memory!
For this reason, AHB spec. constraints that one incrementing transfer should not cross 1KB boudary.
1 kilobyte is the smallest area an AHB slave may occupy in the memory map. Therefore,if a burst did cross a 1 kilobyte boundary, the access could start accessing one slave at the beginning of the burst and then switch to another on the boundary, which must not happen for the above reason.
The 1 kilobyte boundary has been chosen as it is large enough to allow reasonable length bursts, but small enough that peripherals can be aligned to the 1 kilobyte boundary without using up too much of the available memory map.